A vulnerability discovered in the Border Gateway Protocol could allow an attacker to sniff all traffic destined for a block of IPs virtually undetected.

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For all the viruses, malware, and exploits that crawl around the web, fundamental flaws in the system are supposed to be few and far between, but the last two months have proven to be an exception to the rule. In July, Dan Kaminsky revealed his discovery of a DNS flaw that could be exploited to direct unwitting users to malicious web addresses, Now, practically on the heels of that announcement, a hacker team that presented at DEFCON has demonstrated how a fundamental design error in the Internet's border gateway protocol (BGP) can be used to invisibly eavesdrop on all traffic originating from a particular set of IP blocks.